Apicultural Issues – from pesticides to land use change
Norman Carreck, the International Bee Research Association’s science director, tells PEN about some of the challenges facing bee colonies – from pesticides to land use change
Internationally recognised as the world’s primary source and foremost provider of information on bees, the International Bee Research Association (IBRA) promotes the value of bees by providing information on bee science and beekeeping worldwide. It has one of the largest databases of scientific information on bees and bee-related interests in the world, and information services, including journals, teaching aids and other publications, embrace all bee species whether they’re managed by man for pollination or their products, or are truly wild.
Pan European Networks asked IBRA’s science director, Norman Carreck, about the association’s activities and some of the challenges facing bees around the world today.
There are around 630,000 beekeepers and 16 million hives in the EU, producing 234,000 tonnes of honey each year. How then, would you characterise both the support for the sector and the challenges it faces in Europe today?
The challenges will vary from country to country, as will the levels of support; in some EU countries honey is a big commercial operation (such as in parts of France and Spain) while in other areas there are a vast number of amateur beekeepers (such as Slovenia, which has a high density of small beekeepers, as well many different beekeeping associations, but very few commercial honey producers).
Through its agriculture programme, the EU provides a sum of money which is allocated to a country on the basis of how many hives they have. There are a number of areas that qualify for aid and it is up to individual member states to decide how to allocate that money. In some countries, it is spent on research; in others, it is spent on treatments against the parasitic varroa mite, while in others still it is spent on subsidies on sugar.
The issue of pesticides is a very complicated one, despite it being portrayed in the media as being very simple. Generally speaking, there is very good evidence that many bee species have seen a decline in their populations over the past hundred years or so, a number of these species are threatened, while a number have become extinct in various places. However, it is worth noting that the ones that have done particularly badly tend to be those that were quite rare to start with, while some common species of bee appear to be just as common as they have ever been.
In Britain, for example, there is a new species of bumble bee that arrived some 20 years ago and is doing incredibly well, having spread from where it was first discovered in the south of England to now being found near the north of Scotland. At the same time, several bumble bee species became extinct in Britain in the last hundred years and one is now subject to a reintroduction programme, some other species became extinct about 150 years ago, meaning that these extinctions pre-date modern pesticides and agriculture. There is no doubt, however, that modern agriculture has increased the rate of decline.
Scientists are pretty much in consensus that the major driver for bee declines is changes in land use, meaning that wild bees have fewer places to nest and less food. That is a long-term driver, on top of which there are short-term changes, such as those caused by weather conditions (bee populations always fluctuate from year to year because of weather conditions) as well as a whole host of other interacting factors such as pests and diseases. In the case of the honey bee, the most important pest is the parasitic varroa mite, which transmits a number of different viruses. Of course, there is also the issue of pesticides, and most bee scientists agree that while pesticides are somewhere in the mix of factors, few would place them at the top of that list.
The first issue of our journal Bee World from 1919 contains an article about the pesticide poisoning of bees in Canada. It discusses heavy metal compounds such as copper arsenate being used to spray apple trees, and even then there was a debate around to what extent pesticides were a problem.
Around the time of the Second World War, synthetic pesticides began to emerge, such as organochlorines, including the notorious DDT (although early research demonstrated that DDT was less harmful to bees than the chemicals that had been used previously).
Then, and particularly in the 1970s, organophosphorus compounds, which were very harmful to bees, started to be used. In Britain, when farmers started growing a lot of oilseed rape, losses of bee colonies due to poisoning were extensive. Then, during the 1980s onwards, different and safer classes of compounds came in – first were carbamate compounds and then synthetic pyrethroids, which rapidly became the most commonly used insecticide. However, although it can be demonstrated that they are harmful to bees in the laboratory, they actually have a repellent effect on bees, meaning that bees don’t come into contact with them in the field. In practice, these chemicals have proved to be very safe for bees in terms of not destroying colonies, although they may have more subtle effects.
The 1990s saw the introduction of neonicotinoids, which are very toxic to bees in the laboratory but are generally used as a seed dressing. The idea here was that if they are used to coat seeds rather than being sprayed on flowers like earlier pesticides, then they will not come into contact with bees. However, almost as soon as they were introduced in the mid-1990s, beekeepers in France found that their bees were dying and blamed these new insecticides for the damage. Neonicotinoids were being used particularly on sunflowers and oilseed rape, which are very attractive to bees, and there were extensive losses of colonies at the time. In hindsight, however, this was also the time when the parasitic varroa mite became resistant to the compounds that were being used to control it in that part of the world. The symptoms that were being reported, then, were almost certainly those of varroa and not of acute pesticide toxicity. Nonetheless, the French beekeepers were very upset and protested about their use.
There were various restrictions on the use of neonicotinoids, in particular on the compound imidacloprid, which was marketed under the trade name of ‘Gaucho’. The restrictions were put on its use on maize, sunflowers, and oilseed rape, but the bee losses continued. Then, in 2008, there were a number of incidents in Germany, Slovenia and Italy, where a different neonicotinoid called clothianidin was being used to treat maize against a particular pest and, while this maize seed was being drilled, lots of bee colonies nearby died suddenly.
It emerged that the factory that was dressing the seed with the insecticide omitted a vital ingredient that makes the powder stick to the seeds, and as the farmers were using pneumatic seed drills that blow the seed into the ground, they had inadvertently created a cloud of this insecticide dust which was blown by the wind onto nearby oilseed rape, which was then flowering, and lots of bee colonies were killed.
That is a worst case scenario of acute pesticide toxicity, but it was very easy to identify what had gone wrong and the company rightly paid compensation to the beekeepers. The design of seed drills was subsequently improved in an effort to prevent future incidents (although similar events have occurred in the US more recently).
Then, in 2012, the current controversy began when a number of scientific papers were published that showed in laboratory-based studies that neonicotinoids have subtle, sub-lethal effects on bees. The authors of these papers argued that this proves that they are dangerous. My criticism of those studies is that they used unrealistically high doses of those neonicotinoid compounds. Those studies are therefore worst case scenarios, so the key question is: what do bees actually experience in the field? So far, field studies show little or no effect, and there are an increasing number of studies that show no effect in the field at all.
Nevertheless, those initial studies were sufficient enough to raise doubts in the minds of the European Food Safety Authority, who imposed a moratorium on their use. Yet, it is worth noting that the moratorium was not based on knowledge that these chemicals are harmful, but on the fact that there were huge gaps in our knowledge.
From the end of 2013, the moratorium was put in place on the use of three of these compounds on what were termed ‘bee friendly’ crops. That moratorium was intended to be for two years, but it remains in place and I suspect it will continue to do so. This has caused a dilemma for farmers who used those compounds to protect their crops from pests. In the UK, farmers have suffered crop failures and extreme pest problems that they have great difficulty controlling, and their use of other insecticides has greatly increased as a result. Insecticide sprays are not particularly effective on some pests that live inside the stems of the growing plants, while some insects are resistant to older compounds. The consequence of the moratorium has thus been greater pesticide usage and, in the UK, a reduction in the area of oilseed rape–a major food source for bees–being grown.
Existing data is held as being insufficient to clearly understand the reasons behind why pollinator populations in Europe are in decline. What do you feel needs to be done to rectify this? How can a co-ordinated effort be achieved?
I am involved in an organisation called COLOSS which was originally set up in 2008 as a COST Action. This used a relatively small amount of money to bring a group of researchers together. It began with quite a small group of mainly European bee researchers looking into the different causes of honey bee colony losses, and it is now an independent research association with 858 members from 96 countries worldwide.
These are bee researchers as well as those involved in education, and they have been involved in a lot of major projects such as, for example, the standardisation of the methods for collecting data on colony losses over winter so that it becomes possible to study colonies from different countries. COLOSS has achieved a huge amount, including through other projects that have tackled pests and diseases in particular.
There is almost universal agreement that there is no one single factor that accounts for all colony losses and colony declines; it is a combination of things and, indeed, can often be attributed to different things in different places.
There is now pretty good data that shows that there aren’t consistently higher winter losses in any one country. This demonstrates that beekeepers have adapted to their local conditions, rather than that there is any major geographical effect.
Then, of course, new threats emerge from time to time. For example, the small hive beetle, which is originally from sub-Saharan Africa, found its way to the US some 20 years ago, causing significant problems. It was also found in Italy in 2014, where it has gained a foothold and no doubt will spread. Similarly, a species of hornet from Asia was found in France about 15 years ago and is now spreading, being found in the UK for the first time last year.
What role does a better level of education have when it comes to understanding bees and their place in the environment?
There are essentially three groups that need educating: the beekeepers themselves, the general public (including children), and decision makers. At IBRA, we work to provide information to all of these. In terms of the beekeepers, the surveys, particularly those used in the US which have asked beekeepers to list the reasons why their colonies die, have been very revealing. The reasons they have listed include things like starvation, weak colonies going into the winter, and damage by bears, all of which are preventable: you shouldn’t let your livestock starve; if the colonies are too small going into the autumn you can combine them with others to increase their chances of survival, and so on.
This is the same everywhere, and it is generally agreed that improving the level of beekeeper education in terms of better techniques would have strong rewards in terms of reducing colony losses. Certainly in the UK, a lot of the money that comes from the EU’s agriculture fund, as well as from some national government funding, has been put into education, with the development of beekeeping education packs by the British Beekeepers Association, places on training courses and a new beekeeping apprenticeship scheme run by the Bee Farmers Association.
Politicians of all parties tend to be very sympathetic to bees, but of course, in times when money is tight, bees are not always a top priority. In Britain, there are now National Pollinator Strategies that encourage everyone who owns or manages land to maintain it in a way that is beneficial to pollinators, and this has many good initiatives. Of course, there is no punishment for anyone who doesn’t take part and no money to encourage people to do so, but these strategies are nevertheless in place and are a good basis for perhaps raising money elsewhere.
Alongside education, what other functions does IBRA have?
The International Bee Research Association was set up in 1949 to supply information about bees and beekeeping worldwide, and we are a truly international organisation with members in many countries. We have been involved in various activities in the past, but our primary role is now as publishers of information. We publish two journals – a scientific journal called The Journal of Apicultural Research, which is a peer-reviewed, primary research title, and another called Bee World, which is a more popular journal aimed at being the interface between the primary science and what could be termed ‘the thinking beekeeper’ and has much more accessible articles on beekeeping and scientific topics. These journals are distributed worldwide.
We also publish books, such as one called Plants for Bees, which details all the plants in Britain and western Europe that bees rely on, providing information about their characteristics and whether they are good for honey bees, bumble bees, or solitary bees. Forthcoming books include one on the small hive beetle and another on the Asian hornet, with which we are trying to fill in gaps in the literature. In the past, we have organised conferences and published their proceedings, and we also sell books and provide general information.
We thus have a range of activities, and I don’t see them changing dramatically in the future. Over the last 20 years, we have evolved in order to keep up with changes in information technology and other areas. For instance, our entire back catalogue of journals, right back to 1919 in one case, is now available online and we make use of social media and so on. We have had to adapt considerably, and I am sure we will continue to do so. Our organisation is just as needed now as it was when it started nearly 70 years ago.
International Bee Research Association
Curated from: paneuropeannetworks